JP3287786B2 - Curable silicone composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curable silicone composition capable of imparting excellent release properties and slipperiness to an adherend, and more particularly to a mixture with an organic resin containing an organic solvent. Curable silicone composition.

[0002]

2. Description of the Related Art Conventionally, in order to prevent adhesion or sticking between a substrate such as paper or plastics and an adhesive substance, or
Curable silicone composition as a material to improve the slipperiness between paper and paper, paper and plastics, plastic film and plastic film, paper and human hand, plastics and human hand, plastics and metal, etc. Things are used.

[0003] Such silicone compositions are described, for example, in JP-B-35-13709 and JP-B-36-1397.
As described in JP-A-46-26798, it is widely used as an organic solvent solution or an aqueous emulsion. Among these, the organic solvent solution type requires a large amount of solvent for its use because the main component of the diorganopolysiloxane is raw rubber having a high molecular weight (high degree of polymerization). In addition, there is a drawback that adhesion to a substrate is poor.

On the other hand, the aqueous emulsion type is
Although the problem caused by the use of the solvent is eliminated, there is a risk of secondary pollution caused by the use of the emulsifier, and furthermore, it is necessary to heat at a high temperature for a long time to form a film, which is disadvantageous economically. In order to solve the above drawbacks,
Solvent-free silicone compositions containing no water or organic solvents are described, for example, in Japanese Patent Publication Nos.
-3991, JP-A-51-73054, and 50-
No. 14,1591, for example. However, these have a viscosity of 50 to 5000 cs (2
The use of vinyl siloxane or hydrogen siloxane (5 ° C.) has the disadvantage that the resulting coating is hard and brittle.

In contrast to the above-described method of applying the silicone composition itself to the surface of the substrate, there is a method of internally adding the silicone composition to another organic resin to impart releasability and slipperiness. As the so-called internal addition type release agent, a petroleum wax type, a silicone type or a combination thereof has been conventionally used, but a non-reactive silicone is mainly used in many cases. However, in this case, since the non-reactive silicone release agent migrates, there have been disadvantages that the properties such as the releasability and the slipperiness gradually decrease and that the contacted material is stained.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide excellent workability and environmental adaptability, as well as imparting excellent release properties and slipperiness to an adherend without soiling a contact object. It is an object of the present invention to provide a curable silicone composition for internal addition to an organic resin, which can be used.

[0007]

SUMMARY OF THE INVENTION The above objects of the present invention are as follows.
(A) Organopolysiloxane 10 represented by the following formula 2:
0 parts by weight, and (b) 1 to 50 parts by weight of an isocyanate compound having at least two isocyanate groups in one molecule, wherein the number of hydroxyl groups in the molecule of the component (a) is (B) A curable silicone composition characterized in that the total number of isocyanate groups in one molecule of the component is 5 or more.

[0008]

Embedded image In the formula, R ¹ is a monovalent saturated hydrocarbon group, and R ² is C ₆ H _5- (CH ₂ ) _P
A phenyl-substituted alkyl group represented by -CH (R ⁴ ) -CH _2- , R
³ is a hydroxyl group-substituted alkyl group represented by —CH ₂ —CH ₂ —CH ₂ —O— (C ₂ H ₄₀ ) _q —H, wherein R is R ¹ , R ² and R ³
And R ⁴ represents a hydrogen atom or R ¹ . l is 0 or a positive number, m is a positive number, n is a positive number of 2 or more, and 0.10 ≦ m / (l + m + n) ≦ 0.7
0, 5 ≦ l + m + n ≦ 100, p is a positive number from 0 to 5, q
Is a positive number from 1 to 3.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The organopolysiloxane as a first component constituting the silicone composition of the present invention has at least two hydroxyl-containing alkyl groups in one molecule and has a phenyl group-containing organic group among all organic groups. About 5 to 3 alkyl groups
Although it contains 0 mol%, it is particularly preferable to be a linear siloxane represented by the following chemical formula (3).

[0010]

Embedded image

R ¹ is a monovalent saturated hydrocarbon group such as a methyl group and an ethyl group, and is particularly preferably a methyl group. R ² is phenyl represented by C ₆ H ₅ — (CH ₂ ) _P —CH (R ⁴ ) —CH ₂ — (p is a positive number from 0 to 5, and R ⁴ is a hydrogen atom or R ¹ ) A group-containing alkyl group, wherein R ³ has the formula —CH ₂ —CH ₂
The _{-CH 2 -O- (C 2 H 4} 0) q -H hydroxyl group-containing alkyl group (q is from 1 positive number of 3) represented by a hydroxyl group-substituted alkyl group containing 2 or more. Also, the degree of polymerization (l + m +
n) is 5 to 100, preferably 10 to 50.

The molecular structure of the organopolysiloxane may be linear or branched, as long as the object or effect of the present invention of obtaining the above characteristics is achieved. and it is possible to control the compatibility and bleedout resistance with the organic resin by increasing or decreasing the R ^2.

The second component constituting the silicone composition of the present invention
The isocyanate compound as a component reacts with a hydroxyl group of the polysiloxane as the first component to crosslink the first component. Such a compound is not particularly limited as long as it is a low molecular weight polyisocyanate compound having at least two isocyanate groups in one molecule.
Specific examples thereof include, for example, triphenylmethane triisocyanate, diphenylmethane diisocyanate,
Tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and the like.

The amount of the second component relative to the first component may be determined according to the amount of the hydroxyl group contained in the first component. It is used in an amount of 1 to 50 parts by weight per 100 parts by weight of one component. The composition of the present invention is obtained by blending a predetermined amount of the first and second components,
If necessary, an amine-based or organotin-based compound may be used as a catalyst for further promoting the reaction.

Since the curable silicone composition of the present invention utilizes a urethanation reaction, it has good compatibility with many organic resin components, especially in a solution. Therefore, for example, by adding to an organic solvent solution of an organic resin such as a polyester resin, a urethane resin, a PVC resin, a vinyl acetate resin, and an alkyd resin, papers such as polyethylene laminated paper and glassine paper, and plastic films such as polyolefin and polyester And can be easily applied to molded products.

The coating is performed using a roll coater, a gravure coater, an air coater or the like when the substrate to be coated is a flat substrate, or brushing when the substrate is a three-dimensional substrate.
It can be performed using a known coating technique such as spraying and dipping. The coated material thus obtained is
Dry and cure at room temperature or by heating to form a cured film on the substrate surface.

The film obtained in this way has excellent adhesiveness to a substrate as compared with a film formed of a silicone composition alone, and hardly causes poor curing which occurs when using an addition type composition. There are advantages too. In addition, the use of a non-curing type release agent has the characteristic that the change in characteristics is small and the surface to be contacted is not stained, so that the range of application can be expanded.

[0018]

According to the present invention, the curable silicone composition of the present invention is mixed with an organic resin, applied to various substrate surfaces, and dried to form a cured film having good heat resistance, release properties and slipperiness. It can be obtained, and since the release agent does not migrate, the adherend is not contaminated.

[0019]

Next, the present invention will be described in more detail by way of examples, which should not be construed as limiting the present invention. In the examples, parts are parts by weight, and viscosities represent values measured at 25 ° C. The coatings obtained in Examples and Comparative Examples were evaluated as follows.

After applying a predetermined amount of the curable composition to the surface of a 50 μm polyester film, the coating is heated for a predetermined time in a hot air circulating drier at a predetermined temperature, and the coated surface is rubbed with a finger to determine whether or not the coating has fallen off and cloudy. Was determined.

After a predetermined amount of the release composition was applied to the surface of a 38 μm polyester film, it was heated for a predetermined time in a hot air circulating dryer at a predetermined temperature to form a cured film. Next, a polyester tape (trade name: Knit-31B, manufactured by Nitto Denko Corporation) was adhered to the cured film, aged at 70 ° C. for 20 hours under a load of 20 g / cm ² , and then 180
Peeling was performed under the conditions of an angle of ° C and a peeling speed of 0.3 m / min, and a force [g] required for peeling was measured.

After a cured film of the composition was formed on the surface of the sheet-like substrate in the same manner as in the slipperiness release test, 200 g of styrene-butadiene rubber (SBR) under a load of 200 g was placed on the surface. This was pulled in parallel with the silicone surface at 0.3 m / min, the force (g) required at that time was measured, and the force required for pulling / 200 was calculated as the dynamic friction coefficient (AS
According to TMD 1894-63). In addition, with respect to this slip, the sliding property was relatively determined by moving a hand on the above-mentioned cured film according to the following criteria. ◎ ───Slip very well. ○ ───Slip well. × ─── Does not slip. ×× ── No slip.

Synthesis Example 1. An organohydrogenpolysiloxane represented by the following formula 4 was prepared by a conventional method in a 500 ml four-necked flask equipped with a stirrer, a reflux condenser, a thermometer, and a dropping funnel. 94.2 g and 100 g of toluene were added, and the mixture was heated to 90 ° C. and stirred.

Embedded image

While the above heating and stirring were continued, a mixture of 82.6 g of α-methylstyrene and 2 mg of chloroplatinic acid was added dropwise. After completion of the addition, the mixture was reacted at 110 ° C. for 8 hours. Further, a mixture of 67.3 g of allyl glycol and 2 mg of salt platinate was added dropwise at 70 ° C., and the mixture was reacted for 8 hours. By distilling off toluene and unreacted raw materials under reduced pressure, 220 g of a transparent organopolysiloxane A represented by the following formula 5 was obtained.

[0025]

Embedded image The viscosity of the obtained organopolysiloxane A is 2,430.
cp, refractive index 1.497, hydroxyl value 137 KO
Hmg / g. This indicates that about 6 hydroxyl groups exist in one molecule.

Synthesis Example 2 The same apparatus as in Synthesis Example 1 was charged with 98.8 g of an organohydrogenpolysiloxane obtained by a conventional method and represented by the following formula (6) and 100 g of toluene, and heated and stirred at 90 ° C.

Embedded image

While the above heating and stirring were continued, a mixture of 82.6 g of α-methylstyrene and 2 mg of chloroplatinic acid was added dropwise. After the completion of the addition, the mixture was reacted at 110 ° C. for 8 hours. Further, a mixture of 22.5 g of allyl glycol and 2 mg of chloroplatinic acid was added dropwise at 70 ° C., and the mixture was reacted for 8 hours. By distilling off toluene and unreacted raw materials under reduced pressure, a transparent organopolysiloxane B19 represented by the following formula 7 is obtained.
0 g was obtained.

[0028]

Embedded image The viscosity of the obtained organopolysiloxane B is 4,830.
cp, refractive index 1.493, hydroxyl value 54KOH
mg / g. This indicates that about 8 hydroxyl groups exist in one molecule.

Synthesis Example 3 99.1 g of an organohydrogenpolysiloxane represented by the following formula 8 was used as the organohydrogenpolysiloxane, and α-
Except that the amount of methylstyrene used was halved to 41.3 g, the same procedure as in Synthesis Example 1 was carried out to obtain 190 g of a transparent organopolysiloxane C represented by the following chemical formula 9.

[0030]

Embedded image

Embedded image The viscosity of the obtained organopolysiloxane is 2,450 c.
p, refractive index is 1.475, hydroxyl value is 139 KOH
mg / g. This indicates that there are about 6 hydroxyl groups in one molecule.

Embodiment 1 A mixture of 100 parts of the organopolysiloxane A obtained in Synthesis Example 1 and 20 parts of tolylene diisocyanate was added to a saturated polyester resin (Vylon 200:
2 parts were added to 100 parts of a 20% dispersion of toluene / methyl ethyl ketone (1: 1) manufactured by Toyobo Co., Ltd.). The resulting solution was applied to the surface of a 38 μm polyester film using a # 3 wire bar, and was thermally cured in a hot air circulating dryer at 120 ° C. for 60 seconds. The slip property was examined. The results are shown in Table 1 together with the surface characteristics of the polyester film.

[0032]

[Table 1]

Embodiment 2 FIG. A mixture of 100 parts of the organopolysiloxane B obtained in Synthesis Example 2 and 10 parts of tolylene diisocyanate was added to a saturated polyester resin (Vylon 200:
Two parts were added to 100 parts of a 20% dispersion of toluene / methyl ethyl ketone (1: 1) manufactured by Toyobo Co., Ltd.). The obtained solution was applied to the surface of a 38 μm polyester film using a # 3 wire bar, and thermally cured at 120 ° C. for 60 seconds in a hot-air circulation dryer. The results of the release properties, slipperiness, and the like of the obtained cured film are as shown in Table 1.

Embodiment 3 FIG. A mixture of 100 parts of the organopolysiloxane C obtained in Synthesis Example 3 and 15 parts of tolylene diisocyanate was added to a 20% toluene / methyl ethyl ketone (20%) of a vinyl chloride-vinyl acetate copolymer (Eslec M: trade name, manufactured by Sekisui Chemical Co., Ltd.). 1/1) 2 parts were added to 100 parts of the dispersion. The resulting solution was applied to the surface of a 38 μm polyester film using a # 3 wire bar, and was thermally cured at 120 ° C. for 60 seconds in a hot air circulation dryer. The results of the obtained cured film, such as releasability and slipperiness, are as shown in Table 1.

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shunji Aoki 1-10 Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (56) References JP-A-1-197518 (JP, A) JP-A-7-165925 (JP, A) JP-A-2-115817 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 18/00-18 / 87 C08L 83/06

Claims (1)

(57) [Claims] 1. A composition comprising (a) 100 parts by weight of an organopolysiloxane represented by the following formula (1) and (b) 1 to 50 parts by weight of an isocyanate compound having at least two isocyanate groups in one molecule. Wherein the number of hydroxyl groups in one molecule of the component (A) and one of the components (B)
A curable silicone composition, wherein the total number of isocyanate groups in the molecule is 5 or more. Embedded image In the formula, R ¹ is a monovalent saturated hydrocarbon group, and R ² is C ₆ H _5- (CH ₂ ) _P
A phenyl-substituted alkyl group represented by -CH (R ⁴ ) -CH _2- , R
³ is a hydroxyl group-substituted alkyl group represented by —CH ₂ —CH ₂ —CH ₂ —O— (C ₂ H ₄₀ ) _q —H, and R is R ¹ , R ² and R ³
And R ⁴ represents a hydrogen atom or R ¹ . l is 0 or a positive number, m is a positive number, n
Is a positive number of 2 or more, and 0.10 ≦ m / (l + m + n)
≦ 0.70, 5 ≦ l + m + n ≦ 100, p is a positive number from 0 to 5, and q is a positive number from 1 to 3.